Righton D, Garzon F, Hawkes L A, Hicks R, Horton T, Ives M, Katsiadaki I, McCully Phillips S R, Roslyn S, Sebire M, Stone D, Witt M J, Wright S, McKeown N J
Centre for Environment, Fisheries and Aquaculture Science, Pakefield Road, NR33 0HT, Lowestoft , Suffolk, England.
School of Environmental Sciences, University of East Anglia, Norwich, Norfolk, NR4 7TJ, UK.
Sci Rep. 2025 Feb 11;15(1):5018. doi: 10.1038/s41598-025-87053-0.
In fisheries, genetic based assignment of individuals to their population of origin can benefit efforts aimed at monitoring and managing stocks. Assignment combined with knowledge of the migration history of individuals can provide powerful insights into mechanisms of genetic mixing, for which refined sampling methods are required to minimise any impacts. In this study we tested two minimally invasive swabbing techniques for sampling DNA when attaching electronic satellite tags to Atlantic bluefin tuna (Thunnus thynnus) for migration studies. First, DNA was sampled by skin swabbing (hereafter skin swabs) individuals from which there were corresponding fin clip samples. Second, swabs were taken from the applicator poles used to attach electronic tags (hereafter pole swabs). Quantification of DNA from the different sources revealed decreasing yields moving from fin clips, to skin swabs, to pole swabs. The utility of the DNA obtained by both swabbing methods for individual genotyping was then assessed by sequencing of the mtDNA control region and genotyping of six microsatellite loci. In all cases successful genotyping was achieved. For mtDNA an 868 bp fragment was successfully amplified in all samples with 775 bp aligned across individuals revealing 26 haplotypes (overall haplotype diversity = 0.987). All six microsatellites were successfully amplified including a largest allele size of 291 bp. mtDNA and microsatellite genotypes for the skin swabs matched with the corresponding fin clip samples. Although no tissue replicates were available for the pole swab samples the genotypes obtained were unambiguous, consistent across repeated PCRs, and reported no evidence of PCR issues such as large allele drop out. Overall, the genetic data suggested high variability among individuals sampled, comparable to levels of genetic diversity seen within the species' Atlantic range. The study demonstrates that non-invasive sampling can be used to obtain DNA for population assignment studies and that valuable material can be sampled from tagging equipment.
在渔业中，基于遗传信息将个体归属于其起源种群有助于实现种群监测和管理目标。结合个体洄游历史信息的归属分析能够为基因混合机制提供有力的见解，而这需要精细的采样方法以尽量减少任何影响。在本研究中，我们测试了两种微创拭子采样技术，用于在为洄游研究给大西洋蓝鳍金枪鱼（Thunnus thynnus）附着电子卫星标签时采集DNA。首先，通过擦拭个体皮肤（以下简称皮肤拭子）来采集DNA，这些个体同时还采集了相应的鳍条样本。其次，从用于附着电子标签的涂抹杆上取样（以下简称杆拭子）。对不同来源的DNA进行定量分析后发现，从鳍条样本到皮肤拭子再到杆拭子，DNA产量逐渐降低。然后，通过对线粒体DNA控制区进行测序以及对六个微卫星位点进行基因分型，评估了两种拭子采样方法所获得的DNA用于个体基因分型的效用。在所有情况下均成功实现了基因分型。对于线粒体DNA，所有样本均成功扩增出一个868 bp的片段，个体间比对后有775 bp的片段对齐，共揭示出26种单倍型（总体单倍型多样性 = 0.987）。所有六个微卫星位点均成功扩增，其中最大等位基因大小为291 bp。皮肤拭子的线粒体DNA和微卫星基因分型与相应的鳍条样本匹配。尽管杆拭子样本没有可用的组织重复样本，但所获得的基因分型结果明确，在重复PCR中保持一致，且未报告存在诸如大等位基因缺失等PCR问题。总体而言，遗传数据表明所采样个体间存在高度变异性，与该物种在大西洋范围内的遗传多样性水平相当。该研究表明，非侵入性采样可用于获取用于种群归属研究的DNA，并且可以从标记设备上采集到有价值的样本材料。
